Added role to manage the hosts file

roles/hostsfile/defaults/main.yaml

@@ -0,0 +1,32 @@
+---
+hostsfile_loopback:
+  127.0.0.1:
+    - localhost
+    - localhost.localdomain
+    - localhost4
+    - localhost4.localdomain4
+  ::1:
+    - localhost
+    - localhost.localdomain
+    - localhost6
+    - localhost6.localdomain4
+    - ip6-localhost
+    - ip6-loopback
+
+hostsfile_self:
+  "{{ ansible_default_ipv4.address }}":
+    - "{{ ansible_fqdn }}"
+  "{{ ansible_default_ipv6.address }}":
+    - "{{ ansible_fqdn }}"
+
+hostsfile_routers:
+  ff02::1:
+    - ip6-allnodes
+  ff02::2:
+    - ip6-allrouters
+
+hostsfile_hosts: {}
+
+hostsfile_combined: "{{ hostsfile_loopback
+                        | combine(hostsfile_hosts)
+                        | combine(hostsfile_self) }}"

roles/hostsfile/tasks/main.yaml

@@ -0,0 +1,8 @@
+---
+- name: configure hosts file
+  template:
+    src: hosts.j2
+    dest: /etc/hosts
+    owner: root
+    group: root
+    mode: 0644

roles/hostsfile/templates/hosts.j2

@@ -0,0 +1,33 @@
+# {{ ansible_managed }}
+
+{% macro render(hosts, comment=None) %}
+{% if hosts is defined and hosts | length %}
+{% if comment is not none %}
+# {{ comment }}
+{% endif %}
+{% for ip, names in hosts.items() | default({}) %}
+{{ ip }} {{ names | join(' ') }}
+{% endfor %}
+{% endif %}
+{% endmacro %}
+
+{{ render(hostsfile_loopback, comment="Loopback") }}
+{{ render(hostsfile_routers, comment="Routers") }}
+
+# Self
+{% if 'address' in ansible_default_ipv4 %}
+{{ ansible_default_ipv4.address }} {{ inventory_hostname }} {{ inventory_hostname_short }}
+{% endif %}
+{% if 'address' in ansible_default_ipv6 %}
+{{ ansible_default_ipv6.address }} {{ inventory_hostname }} {{ inventory_hostname_short }}
+{% endif %}
+
+# Gateways
+{% if 'gateway' in ansible_default_ipv4 %}
+{{ ansible_default_ipv4.gateway }} gateway
+{% endif %}
+{% if 'gateway' in ansible_default_ipv6 %}
+{{ ansible_default_ipv6.gateway }} gateway6
+{% endif %}
+
+{{ render(hostsfile_hosts, comment="Hosts") }}